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INFO: rcu detected stall in cpu_stopper_thread

Status: closed as invalid on 2018/09/05 12:51
Subsystems: kernel
[Documentation on labels]
First crash: 2452d, last: 2400d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in cpu_stopper_thread (2) kernel 7 222d 271d 0/28 auto-obsoleted due to no activity on 2024/11/05 09:18

Sample crash report:
TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'.
sched_clock: Marking unstable (366854437198, -22318)<-(366950920475, -96505603)
INFO: rcu_sched detected stalls on CPUs/tasks:
	(detected by 0, t=100002 jiffies, g=55122, c=55121, q=394)
All QSes seen, last rcu_sched kthread activity 100002 (4295131368-4295031366), jiffies_till_next_fqs=3, root ->qsmask 0x0
migration/0     R  running task    62312    12      2 0x80000008
Call Trace:
 <IRQ>
 sched_show_task+0x600/0x730 kernel/sched/core.c:5332
 print_other_cpu_stall kernel/rcu/tree.c:1441 [inline]
 check_cpu_stall kernel/rcu/tree.c:1559 [inline]
 __rcu_pending kernel/rcu/tree.c:3244 [inline]
 rcu_pending kernel/rcu/tree.c:3291 [inline]
 rcu_check_callbacks+0x2627/0x2990 kernel/rcu/tree.c:2646
 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636
 tick_sched_handle kernel/time/tick-sched.c:164 [inline]
 tick_sched_timer+0x3a6/0x500 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0xbfc/0x15b0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x458/0x13d0 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt+0x6b/0x250 arch/x86/kernel/apic/apic.c:1028
 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1056
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:868
 </IRQ>
RIP: 0010:rep_nop arch/x86/include/asm/processor.h:658 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:663 [inline]
RIP: 0010:multi_cpu_stop+0x244/0x640 kernel/stop_machine.c:202
Code: 45 31 ed 48 89 5d 90 eb 1f 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 e8 2b b5 05 00 45 89 e7 89 5d cc 45 89 f5 48 8b 5d 90 f3 90 <48> 83 7d b8 00 75 6a 44 8b 33 48 89 df e8 9a 07 5f 00 44 8b 20 8b 
RSP: 0018:ffff8801d465fca0 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff815fce95 RBX: ffff8801d44ffac0 RCX: ffff8801d44ed880
RDX: 0000000000000000 RSI: aaaaaaaaaaaab000 RDI: ffffea000af9dfa0
RBP: ffff8801d465fd58 R08: 0000000000480020 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff815fcc60 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000
 cpu_stopper_thread+0x34f/0x750 kernel/stop_machine.c:501
 smpboot_thread_fn+0x4ad/0x9b0 kernel/smpboot.c:164
 kthread+0x44d/0x480 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:415
rcu_sched kthread starved for 100002 jiffies! g55122 c55121 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
RCU grace-period kthread stack dump:
rcu_sched       R  running task    61848    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2857 [inline]
 __schedule+0x667/0x770 kernel/sched/core.c:3507
 schedule+0x1bc/0x2d0 kernel/sched/core.c:3551
 schedule_timeout+0x3f0/0x580 kernel/time/timer.c:1801
 rcu_gp_kthread+0x1da1/0x3850 kernel/rcu/tree.c:2179
 kthread+0x44d/0x480 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:415

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/20 23:23 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/06/29 10:40 https://github.com/google/kmsan.git master 123906095e30 dba0b50e .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.